Now they are tracking you and your surfing habits even more than Google (because it's the OS doing the tracking) and they are going to shove ads in your face any way they can.
Recently it appears that TiVo, of all companies, has started to aggressively insert advertisements onto the screen when you're watching the TV shows you recorded. Rumor has it that Nest thermostats will soon be displaying advertisements on its display.
The computer companies seem to have been taken over by the advertisers. Microsoft is probably just jumping on the bandwagon to get some of the money.